Monitoring of patient cardio-respiratory events is of vital clinical importance in the early detection of potentially fatal conditions. Current technologies that involve contact sensors require that the individual wears such devices constantly. Such a requirement can lead to discomfort, psychological dependence, loss of dignity, and may even cause additional medical issues such as skin infection when sensors have to be worn for an extended period of time. Elderly patients, infants, and those suffering from chronic medical conditions are more likely to suffer from such negative effects of continuous monitoring. The use of an unobtrusive, non-contact, imaging based monitoring of physiological events can go a long way towards alleviating some of these issues.
Previous methods by the authors hereof, and other Xerox researchers, have been directed to systems and methods which employ differing video devices for estimating cardiac and respiratory functions from signals extracted from time-series signals obtained from video of one or more regions of interest of a resting patient. Different imaging devices are utilized because each captures different video signals, each targeted to acquire a different physiological signal, e.g., RGB for heart rate and motion monitoring, thermal for respiration rate and temperature monitoring, and 3D imaging devices for chest volume and minute ventilation estimations. However, each imaging device is also capable of capturing video signals to acquire other physiological signal, for example, RGB for respiration rate, thermal and 3D imaging devices for heart rate estimations. The use of differing video devices to capture video signals that are subsequently fused together to provide a more reliable event monitoring system has its advantages. However, in an integrated imaging system employing a diverse array of different video devices to capture video signals of a subject of interest, Xerox researchers have subsequently determined that differences in the imaging characteristics between an array of video devices need to be taken into account in order to obtain physiological signals for patient event monitoring that are reliable. The teachings hereof are directed to this issue.
Accordingly, what is needed in this art is a video acquisition system comprising N video devices, where N≧2, with each of the video devices capturing a video of a respective region of interest of a subject being monitored for a desired physiological function for continuous physiological event monitoring of the resting patient.